Work has been under way on League Of Legends mobile for more than a year, according to anonymous sources at the game's developers.
An exclusive story by highly respected news agency Reuters reports that a mobile version of LOL is being planned.
League Of Legends developers Tencent Holdings is working with its US arm Riot Games on a mobile version of the world's most popular esport.
The Reuters report referred to an unnamed source who said Tencent and Riot have been working on a mobile version of League of Legends for more than a year - but a separate source said it was unlikely to be launched in 2019.
At the time of publishing, neither Tencent nor Riot had commented.
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There is rumoured tension between Tencent and Riot over the decision to release League Of Legends mobile, with the US unit apparently determined to focus on PC, while Tencent, based in China, are keen to progress with mobile having seen the success of other similar games.
Tencent has enjoyed huge success with PUBG Mobile and, if it is determined to release League Of Legends mobile, it is perhaps prompted by falling revenue.
LOL brought in $1.4 billion in revenue in 2018, although that was down 21% from a year earlier.
Gu Tianyi, of esports market data specialists Newzoo, told Reuters: "League of Legends is not doing as well as it used to and so Riot badly needs a new way to monetise the game, especially considering that it is Riot's only game."
Mobile games account for 57% of gaming revenue in China in 2018 but only 36% in the US market, according to Newzoo.